[ 2o8 ] 



The external charaders and leading properties of the fpecimen 

 which I ufed were the following : 



Colour— Greyifh black, inclining to blue. 



Lustre — o 



Tra*isparency — o 



Hardness— Scratched glafs with difficuhy, crumbling at the 

 fame time. — Did not give fire with fieel. 



Fracture — Lateral fradure imperfedly conchoidal — Tranfverfe 

 fradture flaty, paffing into the coarfe-grained earthy. 



Gave a white ftreak. 



fepFERVESCED with acids. 



Gave an earthy fmell when breathed on. 



When calcined did not flake. 



Colour, when calcined, a yellowifh grey. 



Cracked, nnd flew into thin flates, when expofed to a low heat 

 in an open fire. 



Specific gravity, at the temperature of 66 Fahren}:eit 2. 68. 



CHEMICAL 



